Spinning process and apparatus therefor



Oct. 5, 1937. P. PIERRAT ET AL 2,094,617

SPINNING PROCESS AND APPARATUS THEREFOR Filed Sept. 7, 1954 "J V I4- 7/55 56 I3 HA Paul Piermt Eugcne0lo mbu 221? TTORN Y.

INVENTORS.

Patented Oct. 5, 1937 SFENNHNG rnocnss nun arraaairps rnnnnron.

Paul lPierrat and Eugene Colombo, 'liaris, France,

assignors, by mesne assignments, to E. ii. du Pont de Nemcurs 6*;Company, Wilmington,

Met, a corporation of Delaware Application September '7, 19341, SerialNo. 743.11%

3 @laims.

This invention relates to a process of collect: mg yarn such as freshlyformed artificial silk yarn in a centrifugal spinning bucket and tomeans for traversing the funnel that guides the yarn, thread or likematerial into the rotating bucket. The customary manner of spinning andcollectmg artificial silk thread such as is produced by the viscoseprocess in a centrifugal bucket comprises directing the thread into thebucket through a funnel mounted for vertical reciprocation to distributethe thread between top and bottom of the bucket, which motion incombination with the turning of the bucket causes the thread to bedeposited in the bucket to form a cross wound package, or what is termeda cake of yarn; The reciprocation of the funnel is at a constant rateand at some stage of the building of the cake, the movement of thefunnel 2 and the circumferential size of the cake are such that a threadis deposited adjacent and parallel to previous courses to form'bands' orribbons. These bands will vary in width according to the ratio betweenthe funnel movement and the circumferential size of the cake and attimes may be of considerable width. As a resuit, the .cake does not wellretain its structure during processing and it will not lend itself touniform treatment. Furthermore, when the thread is unwound therefrom, itis apt to sluff or slide oif where ribbons occur in a large mass,

to tangle and to cause excessive waste.

It has been proposed (German Patent No. 552,470) in order to producefirm cakes which are not easily collapsed, to periodically change theangle of intersection between different thread windings. The changingangle of intersection of the thread is brought about by changing theform of the cam which causes the funnel guide to rise and fall atvarying rates of speed. The

changes in speed of the funnel guide are with in one or two strokes, andat some point in the spinning of the cake there will be formed in thecake bands or ribbons such as are formed in the .45 usual method ofspinning bucket cakes and the objections of slufiing and excessivewaste, broken threads, etc. as with other prior art are not overcome.

It is therefore an object of our invention to provide a method and meansfor centrifugally winding thread in the form of a cake of improvedcompactness and free from hand or ribbon formation. Other objects willbe apparent from the description that follows.

Referring to the drawing in which like refer- (Ei. lit-$7.6)

ence characteristics designate like parts throughout: Figs. 1-, 2 and 3are diagrammatic views of various thread traverse control assemblies.

It has been discovered,-in accordance with the presentinvention, thatband or ribbon formation in the centrifugal spinning of artificialthread, can be avoided by varying the rate of reciprocation of thetraverse funnel through which the thread is led into the centrifugalbucket in such a way that there is no substantial coincidence orrepetition in the laying down of the thread. In its preferred form, thisvariation in thread traverse is accomplished by slowly changing thespeed of the cam shaft which operates the funnel traverse mechanism. Inthe drawing, various alternative means for accomplishing this result areshown, but it is-to be understood that the preferred form .isillustrated in Figure 1.

Referring to Figure 1, l is the driving shaft which may or may not bethe main drive shaft of the spinning machine. Attached to it is pinion 2gearing with pinion 3 on shaft i. The latter drives shaft 6 by means ofoppositely disposed conical pulleys 5-A and 5-B and belt 5 as shown.Shaft 5, in turn, drives shaft 9 to which is fastened cam lb. Pinions land 8 fixed to shafts 6 and 9 respectively are for this pur pose. Belt 5passes between the fingers of a fork 5-0 attached to a ring l l'whichslides without revolving on a shaft l3 supplied with both left andright-hand screw threads. Shaft 13 and shaft if to which it is attachedare revolved by means of gears HA and ll-B and shaft 6. Suitableprojections fastened to ring Ml running in the grooves of the leftandright-hand threaded member cause the belt to be shifted continuously oneway and then the other as the ring it travels from one end to the otherof the threaded portion of member it.

The rapidity of the change in funnel speed maybe regulated, of course,in many ways, for instance, by changing the pitch of the cone pulleys,,the pitch of the threads or the length of the threaded portion onmember l3, or by changing the size of gears H--A and llB.

With the arrangement just described and shown in Figure 1 of thedrawing, the cycle which comprises the travel of the belt 5 from oneextreme position, for example, at the left, to the other extremeposition and back again, will be very slow and will preferably coverthat period within whichthe funnel guide takes at'least strokes. It willbe understood that this cycle may cover a period of several hundredstrokes, or for that matter, even less than 100 strokes of the funnelguide. As further illustration of means for varying the speed of thefunnel guide in a manner similar to that just described, reference ismade to the diagrammatic systems shown in Figures 2 and 3.

In Figure 2, 20 is a main drive motor which serves only for the funneltraverse motion in the spinning machine. This motor is a variable speedmotor and is controlled by a variable resistance 2| through a gear train22, 23, shaft 24 and gears 25 and 26 driven from the motor shaft 2! asshown. Cam 32 is fixed to gear 3| and by means of a gear train 28, 29and 30 connecting with gear 3|, the main shaft 21 of the motor causescam 32 to revolve. Cam 32 operates the funnel traverse bar and thefunnel guide mounted thereon through the traverse bar lifter rod 34 andsuitable linkage 35, 36, 31 and 38 illustrated diagrammatically, thefunnel guide. being reciprocated at constantly varying rates of the samecharacter as described in connection with Figure 1.

In Figure 3 a set-up similar to that just described is shown, butinstead of using a variable speed motor, a constant speed motor may beused and the cam driven through a suitable gear train 40, 4|, 42 and 43that is connected to the motor through a variable speed drive 44 such asa drive of the Reeves or a PIV type having a suitable variable speedcontrol box 45.

A conventional traverse bar with an accompanying funnel guide 5| hasbeen shown con-' nected to' the lifter rod 34. The funnel guide 5| isshown projecting into a spinning pot in a known manner.

From the description given above of the various means for producing thedesired results, it is to be noted that the change in funnel speed takesplace very slowly. In other words, there is no perceptible change fromone stroke to another, nor within the stroke. It is preferred that thechange takes place within a cycle which comprises from to 1000 or morestrokes of the guide funnel, which change will not appreciably alter theshape of the cake or appreciably change the angle at which variousadjacent layers of the threads cross, but which will prevent synchronismbetween the movement of the funnel and the rotation of the bucket andthereby pre- While the invention has been described in its I applicationto the production of regenerated cellulose thread or the like producedfrom viscose, it is equally applicable to any centrifugal spinningprocess such as for instance the spinning of cuprammonium cellulosethreads, or other cellulose derivative threads or to textile threads ofany description that are collected in rotating buckets as cross-woundcakes.

We claim:

1. In an apparatus for regulating the speed of traverse of the funnelthrough which artificial thread is led into a spinning bucket in acentrifugal spinning process, means for imparting to the funnelreciprocating motion, means for supplying energy to said first namedmeans from an outside source of power, and means intermediate saidbefore mentioned means which constantly changes the speed of said firstmentioned means for a period covering at least fifty strokes of saidfunnel.

2. In an apparatus for regulating the speed of traverse of the funnelthrough which artificial thread is led into a spinning bucket in thecentrifugal spinning process, means connected with the funnel forimparting a traverse motion thereto, a rotating cam shaft having a cammounted thereon for imparting motion to the said means, means forsupplying energy to the said cam shaft in order to rotate the same, andmeans intermediate the cam shaft and the last mentioned means whichcontinuously and slowly changes the speed of the cam shaft.

3. Apparatus as claimed in claim 2 in which the said intermediate meansfor varying the speed of the cam shaft comprises a pulley driving a beltwhich in turn drives another pulley which is connected with the camshaft, such pulleys being frusto-conical inform and inverted withrespect to each other.

. PAUL PIERRAT.

EUGENE COLOMBU.

